Plastic nosing for stairways

ABSTRACT

A PLASTIC STAIR NOSING COMPRISES AN ELONGATED PLASTIC BODY HAVING A NARROW SLOT IN ONE EDGE WHICH EXTENDS SUBSTANTIALLY THE FULL LENGTH OF THE PLASTIC BODY, SO THAT IT IS ADAPTED TO FIT ONTO THE FORWARD LIPPED EDGE OF A METAL PAN STAIR. THE REMAINDER OF THE TREAD PORTION OF THE METAL PAN STAIR COMPRISES CONCRETE OR OTHER FILLER MATERIAL. THE PLASTIC NOSING IS SAFER THAN THE CONVENTIONAL METAL NOSINGS AND NEED NOT BE PAINTED. NO SCREWS, ANCHORS OR WELDING ARE REQUIRED TO HOLD THE NOSING IN POSITION? IT IS SELF-POSITIONING, SELF-LEVELING AND SELF-SUPPORTING.

Jan. 26, 1971 R. H. GRAF PLASTIC NOSING FOR STAIRWAYS 3 Sheets-Shoot 1Filed Nov. 30, I 1967 n /I/ I I v I M2 Jan. 26, 1971 R. H. GRAF3,557,504

PLASTIC NOSINGV FOR SIMRWAYS Filed Nov. 50, 1967 v 3 Sheets-Sheet 2 IJan. 26, 1971 H. GRAF I PLASTIC NOSING FOR STAIRWAYS 3 Sheets-Sheet 3Filed Nov. 30, 1967 United States Patent 3,557,504 PLASTIC NOSING FORSTAIRWAYS Richard H. Graf, Hauppauge, N.Y., assignor to Hooker ChemicalCorporation, Niagara Falls, N.Y., a corporation of New York Filed Nov.30, 1967, Ser. No. 686,934 Int. Cl. E04d 11/16 Cl. 52-179 6 ClaimsABSTRACT OF THE DISCLOSURE A plastic stair nosing comprises an elongatedplastic body having a narrow slot in one edge which extendssubstantially the full length of the plastic body, so that it is adaptedto fit onto the forward lipped edge of a metal pan stair. The remainderof the tread portion of the metal pan stair comprises concrete or otherfiller material.

The plastic nosing is safer than the conventional metal nosings and neednot be painted. No screws, anchors or welding are required to hold thenosing in position; it is self-positioning, self-leveling andself-supporting.

BACKGROUND OF THE INVENTION Metal pan stairs are conventionallyconstructed by providing a metal frame that is comprised of a series oftreads and risers. Normally the metal tread has a forward turned-up lipwhich is the height of the total thickness of the tread-portion of thefinished step. In constructing the stairway, after the metal frame isinstalled, the pan formed by the primary tread and forward turned-up lipis filled in with cement or other filler media, such as terrazzo, toprovide secondary treads. The forward lipped edge serves to support thefiller medium during the hardening process and also to form a strongerforward edge to the finished step. Moreover, the forward lipped edge canbe bent inwardly, toward the secondary tread, to form a leading edge onthe finished step. However, it is difficult to retain paint or othersurface coatings on such metal nosings. Moreover, the metal nosingsreadily wear smooth and become a safety hazard to persons ascending anddescending the finished stairs.

Accordingly, it is an object of this invention to provide a plasticnosing for stairways, especially metal pan stairs provided with concretesecondary treads.

proved stair construction which includes use of the plastic nosing ofthe invention.

These and other objects will become apparent upon reference to thefollowing detailed description.

DESCRIPTION OF THE EMBODIMENT The invention will be further describedwith respect to the accompanying drawings of which FIGS. 1 and 2 arecross-sectional views of a single unit of stair with the plastic stairnosing of the invention in place. FIG. 3 hows a series of stair units asthey would appear in a stair construction in cross-sectional view.

FIG. 1 shows a single unit 10 of a finished stair. The metal stair frameis formed by a primary metal pan tread 12 and riser portions 14extending above and below tread 12. The tread 12 has a forward lippededge comprised of a forward turned-up lip 16 of a lesser height than thetotal thickness of the completed step and provided at its upperextremity with an essentially horizontal extension 18. As shown in thefigure, a given tread 12 and the vertical riser extending above thetread can be formed from one piece of metal and the forward lipped edgeof this 3,557,504 Patented Jan. 26, 1971 tread can be formed by aseparate metal portion that comprises the riser 14 extending from thestep beneath and running continuously to form the turned up lip 16 andextension 18 as depicted. However, this construction detail is optionaland the tread 12, riser 14 turned up edge 16 and extension 18 could beformed from one piece of metal. Stair nosing 20 comprises a slab ofpolyvinyl chloride or other suitable plastic. Nosing 20 has a narrowslot 22 in the edge of the plastic slab which extends substantially thefull length thereof. Generally the plastic nosing is horizontallydisposed as shown, with the width of the upper surface being at leastabout twice the vertical depth of the solid body of plastic. The narrowslot is horizontally disposed in the vertical face of the nosing thatserves as the front or leading edge of the stair on which it isinstalled. This verticle face preferably joins the upper surface in asmooth curved surface, as shown. The vertical rear face 24 can becurved, as shown. In its installed position as shown in FIG. 1, nosing20 is attached via slot 22 to the metal extension member 18. Forming theremainder of the step and forming the secondary tread thereof isconcrete portion 26. In constructing the step, nosing 20 is slipped orsnapped into place on extension member 18, which serves to hold nosing20 in a level position without further support. Thus, no screws, anchorsor welding are required to hold the nosing in position. Then, cement isfilled in to the side of, and beneath, nosing 20 and leveled off to forma horizontal secondary tread that forms a level surface adjoining theupper surface of the plastic nosing 20.

FIG. 2 shows another single unit 30 of a finished stair. The metal stairframe is formed by a primary metal pan tread 32 and riser portions 34extending above and below tread 32. The tread 32 has a forward lippededge comprised of a forward turned-up lip 36 of a lesser height than thetotal thickness of the completed step. Stair nosing 40 comprises a slabof polyvinyl chloride or other suitable plasitc. In this embodiment,nosing 40 has a narrow slot 42 in the forward portion of the lower edgeof the plastic slab, which slot extends substantially the full length ofthe slab. The narrow slot is vertically disposed in the lower face ofthe nosing, and is positioned somewhat back of the front face 43 of thenosing, so that the front face extends over, and at least partiallycovers the forward turned-up lip 36. The front face 43 can extend belowthe lower face of the nosing, as shown. The front face preferably joinsthe upper face in a smooth curved surface, as shown. The vertical rearface can be curved, as shown. The upper face can have a series ofgrooves 45 to improve the non-slipping quality of the nosing. In itsinstalled position as shown in FIG. 2, nosing 40 is attached via slot 42to the forward turned-up lip 36. The remainder of the step, and formingthe secondary tread thereof, is concrete portion 46.

FIG. 3 shows a series of stair units in place, with step or stair unit10 being substantially as described with respect to FIG. 1. Stair unitis a typical unit adapted to serve as the top step of a stairconstruction so that it properly adjoins the floor or roof at the top ofthe stairs. Thus, primary metal pan tread 52 can be suitably connectedsuch as by welding or otherwise to a metal subfloor 53. The concretesecondary tread 56 can be made to be level with a concrete floor portion57. Stair unit 60 represents a typical unit adjoining the floor at thebottom of a stair construction. Riser 64 extends downwardly from stairsection 60 and is aifixed by any suitable means to the supporting floor65.

The preferred type of plastic for use as the stair nosing of theinvention is polyvinyl chloride. However, other normally solid,thermoplastic materials can be used. Other suitable thermoplasticsinclude the polyolefins, such as polyethylene, poly-propylene,copolymers of ethylene with higher olefins polystyrene, thermoplasticbutadiene polymers and copolymers, such as butadiene-styrene blockcopolymers, and other polythenic compositions such as polyvinylchloride-acetate copolymer, polyvinylidene chloride, acrylic polymersand the like.

The plastic nosing of the invention can be produced in conventionalextruder in which the plastic. material is softened or melted andextruded through an orifice having the shape of the desiredcross-section of the plastic nosing. In this regard, the cross-sectionalshapes shown in FIGS. 1 and 2 are intended to be illustrative, but notto limit the invention. Thus, for example, the vertical edge at theopposite side of the nosing from the narrow slot 22 can have variousshapes. As shown in FIG. 3, this face can have a diagonal flat face 66that is slanted downward toward the rear of the stair or a square groovein a vertical face 54 or a curved face 67, as well as curved face 24 anda variety of other curved shapes. Moreover, the lower, horizontallydisposed face of the nosing can be exactly parallel to the uppermostface or can be diagonally disposed as shown in FIGS. 1, 2 and 3. Theedge of the nosing that forms the leading edge of the entire stair ispreferably curved to form a smooth transition from the horizontal upperface to the vertical edge that fits atop the forward lipped edge 16 andextension member 18 or forward lipped edge 36. Other variations of theinvention are possible without departing from the underlying principalsof the invention. It is understood that the foregoing embodiments areintended to be illustrative of the invention but not to limit it.

I claim:

1. A stair construction comprised of one or more stair units comprisinga metal riser portion and a step portion, said step portion comprising ametal primary pan tread having a forward turned-up lip of less heightthan the total thickness of the step, a plastic nosing comprising anelongated plastic body having a width of at least about twice thethickness thereof and having a narrow slot in one face of said plasticbody and extending substantially the full length thereof, which slot isengaged onto said turned-up lip so as to maintain the upper surface ofsaid plastic body in a substantially horizontal position; and asecondary tread which fills the cavity formed by the primary metal pantread and said plastic nosing.

2. In a metal pan stair construction, the improvement which comprises aplastic nosing comprising an elongated plastic body having a width of atleast twice the thickness thereof and having a narrow slot in one faceof said plastic body and extending substantially the full lengththereof, said narrow slot engaged onto the forward lipped edge of themetal pan tread of said metal pan stairs so as to maintain said plasticnosing in substantially horizontal position.

3. A stair construction comprised of one or more stair units comprisinga metal riser portion and a step portion; said step portion comprising ametal primary pan tread having a forward turned-up lip of less heightthan the total thickness of the step wherein said lip has a metalextension member protruding from its upper extremity; a plastic nosingcomprising an elongated plastic body having a width of at least abouttwice the thickness thereof and having a narrow slot horizontallydisposed in a vertically disposed face of said plastic nosing andextending substantially the full length thereof, which slot is engagedonto said extension member so as to maintain the upper surface of saidplastic body in a substantially horizontal position, and wherein saidvertically disposed face joins the horizontally disposed uppermost faceof said plastic nosing in a curved surface; and a secondary tread whichfills the cavity formed by said primary metal pan tread and said plasticnosing.

4. The stair construction of claim 3 wherein the plastic is polyvinylchloride.

5. A stair construction comprised of one or more stair units comprisinga metal riser portion and a step portion; said step portion comprising ametal primary pan tread having a forward turned-up lip of less heightthan the total thickness of the step; a plastic nosing comprising anelongated plastic body having a width of at least about twice thethickness thereof and having a narrow slot vertically disposed in thelower face of the said plastic nosing, which slot extends substantiallythe full length thereof and which slot is engaged onto said turned-uplip so as to maintain the upper surface of said plastic body in asubstantially horizontal position, and wherein the vertically disposedface adjacent said narrow slot joins the horizontally disposed uppermostface of said plastic nosing in a curved surface; and a secondary treadwhich fills the cavity formed by said primary metal pan tread and saidplastic nosing.

6. The stair construction of claim 5 wherein the plastic is polyvinylchloride.

References Cited UNITED STATES PATENTS 1,545,181 7/1925 Bechtel 52-1881,557,285 10/1925 Hughes 52179 1,674,713 6/1928 Brooks 52179 2,654,91910/1953 Marvin 52-716X 3,334,456 8/1967 Naka 52179 FOREIGN PATENTS222,295 1959 Australia 52-179 1,266,664 1961 France 52-181 586,409 1947Great Britain 52179 JOHN E. MURTAGH, Primary Examiner US. Cl. X.R. 52181

